In a dramatically different approach, light-front holography (LFH) determines the effective potential based on a unique mapping between the equation of motion of the string modes in the Anti-de Sitter (AdS) space [1]} and the light-front Schrödinger equation of hadrons, as consistent with the conformal quantum mechanics and supersymmetry [2]}. This semiclassical approximation is phenomenologically successful in hadron spectroscopy [3]}, [4]}, [5]}, [6]}, including tetraquarks and exotica [7]}, [8]}, form factors [3]}, [10]}, [11]}, and parton distributions[12]}, [13]}. See Refs. [14]}, [15]} for recent reviews.
